We have removed the pebble dash from our 1890s two-storey terraced house and had the brickwork repointed. Since doing so, we have discovered damp in the front bedroom wall. We have had the stonework resealed twice, but damp patches still appear whenit rains. Advice from builders has been contradictory: one said the guttering and roof were okay, but sealed a window; another replaced two slates and said we needed a new roof. A loft inspection did not reveal any leaks and we don’t seem to have cavity walls. What is the problem?

Anne Ellis, Millhead, Lancs

I’m not familiar with the particular brick sealer you used, but you should check that it allows bricks to “breathe” and moisture to dry out. If it does, and if the pointing has been done properly, try replastering internally. Bonding may have been used on the inner side of the outside wall, instead of a sand-and-cement render coat, before it was skimmed. This absorbs moisture – indeed, attracts it. Hack off the affected area, and continue hacking if you find anything other than the correct render; then replaster using sand and cement with a waterproof additive. This should solve the problem. It’s best to do the entire wall, otherwise you may just move the damp patch on.

Q We want to maximise the sale price of our two-bedroom bungalow in Shropshire before retiring to the more expensive Cornish coast in three years’ time. Should we convert the loft into two bedrooms and an ensuite bathroom, and if so, how soon should we do it? We must take out a loan to pay for the work. Also, is it worth paying £1,750 to restore our living room’s parquet floor?

Aled and Gerry Williams, via e-mail

The answer is simple: really get to know the local market. The research required takes considerable time, so ask local agents for their opinion – but only those you really trust. It all depends on whether or not the cost of the loft conversion exceeds what it adds in value. Monitor similar local properties that come up for sale – see what their asking price is, then what they really sell for, and what state they were in. I don’t think restoring the floor will add much value, but, given that you don’t plan on moving for a while, do it and enjoy the results yourselves.

Q I have paid £128,000 for a two-bed, new-build, town-centre flat near Glasgow airport, and plan to let it to young professionals. How much should I spend on furnishing it, and what sort of flooring and curtains would be hard-wearing, attractive and budget-conscious?

Priyank Vashishtha, via e-mail

There is no set budget, but what you install must suit your market. For ease of maintenance, use a wooden floor in the sitting room, a vinyl covering in the kitchen and bathroom, and carpet in the bedrooms. The colours and style are up to you, but make sure the design matches the style of the room. For continuity, use the same ready-made curtains throughout; there are plenty of stylish, affordable versions available online or from stores such as Ikea or B&Q.

Q Clothes, furniture and fitted carpets all continually go mouldy in our 1960s bungalow, which has an almost-flat felt roof, no loft space, UPVC double glazing, gas central heating and cavity-wall insulation. The smell is terrible, and the problem is particularly acute in one room with three outside walls. We have moved our wardrobes away from walls, installed a hot-water pipe around the floor space created, put perforated panels at the sides of the wardrobes so that air can circulate, installed air bricks and window vents in the room worst affected, even invested in a £900 ventilation system – all to no avail. What can we do? We are in our seventies and thinking of selling, as we are at our wits’ end.

Mrs Barbara Wigley, Sheffield

Your home has three problems: an overly high moisture content, poor ventilation and inadequate roof insulation. Buy two dehumidifiers. Relatively inexpensive (many cost less than £100), they suck moisture out of the atmosphere and condense it into liquid water, which you can remove. Also look at your own behaviour. Do you forget to open a bathroom window when you shower or bathe, or boil water a great deal and not use the extractor fan when you do? Do you dry large quantities of wet washing on radiators? Cut the level of moisture you generate and things should improve. Good ventilation is crucial, too, so open those UPVC double-glazed windows regularly. Inspect the vapour point in your roof insulation – where warm air meets cold. If there is no insulation, it needs some; if you have it, and it is wet, then replace it. You need damp-proofing at the point at which hot air (which carries water as a gas within it) turns cold (when the gas turns to liquid). A damp-proof layer – a barrier to stop the damp from penetrating, usually made of plastic – will stop the moisture coming through.

Q We are buying a two-bedroom, two-bathroom flat off plan. When asked to confirm the electrical plan, I requested one living-room double socket to be moved 1.5 metres and an extra double socket installed in the second bedroom. This is possible, apparently – if I pay £300, plus Vat, per socket. The developers say that the contractors are demanding the money, and that, unless I pay immediately, nothing can be done. Given that the flat is only at breeze-block stage, with no interior plaster work or floors, I feel I am being fleeced.

Faga Speker, via e-mail

Such a demand is not uncommon, but it does seem remarkable, given what stage your development is at. Even small changes have a knock-on effect, but you were asked whether or not you wanted changes, and the first-fix wiring has not begun, so expecting a degree of flexibility is not unreasonable. Have your solicitor check your contract – and ensure that the contractors have done everything as they should: if not, you may have a bargaining chip. Failing this, try to gain access at first-fix stage and have your own electrician sort the sockets out. A £600 bill for such minor changes is steep.

Q The front of our home has an extension covered in pebble dash. What can we replace this ugly finish with?

Susan Heslop, via e-mail

You could hack it off, but that might damage the underlying brickwork. A top layer of render will give a smooth, paintable finish; save work by adding a colorant to the render itself. Alternatively, several layers of a good-quality masonry paint such as Sandtex will smooth out much of the bumpy effect of pebble dash. If these options sound too much like hard work, you could just paint it a more attractive colour.

Q We’re updating our eight-year-old kitchen and have found two firms that will spray-paint our light-oak, solid-wood units for about £2,500. They will collect the doors, paint them and return them in seven days; cornices and plinths will be paintedin situ. We have 23 doors to update – do you think it sounds like a good idea? The units are in top condition, but boring.

Liz and Stan Felstead, Camberley, Surrey

I have never heard of such a service, though, ostensibly, it sounds like a good one. It seems costly, however, given the work involved. A good painter and decorator should be able to achieve the same results for far less. Why not change the tiles, handles and worktops instead? You’ll achieve a totally new look for far less money.

Have you got a question for Sarah Beeny? Send your queries by e-mail to sarah.beeny@sunday-times.co.uk or write to her c/o Home, The Sunday Times, 1 Pennington Street, London E98 1ST

Times recommends

• Second homes: credit crunch casualty or money-spinner?
• How I built my own sliding house
• Top 10 incentives for house buyers